info

• A procedure can be viewed as the equivalent of a REST-endpoint.
• There's no internal difference between queries and mutations apart from semantics.
• Defining router is the same for queries, mutations, and subscription with the exception that subscriptions need to return a Subscription-instance.

Input validation​

tRPC works out-of-the-box with yup/superstruct/zod/myzod/custom validators/[..] - see test suite

Example without input​

tsx

import * as trpc from '@trpc/server';

// [...]

export const appRouter = trpc

.router<Context>()

// Create procedure at path 'hello'

.query('hello', {

`resolve({ ctx }) {`

  `return {`

    ``greeting: `hello world`,``

  `};`

`},`

});

With Zod​

tsx

import * as trpc from '@trpc/server';

import { z } from 'zod';

// [...]

export const appRouter = trpc.router<Context>().query('hello', {

input: z

`.object({`

  `text: z.string().nullish(),`

`})`

`.nullish(),`

resolve({ input }) {

`return {`

  ``greeting: `hello ${input?.text ?? 'world'}`,``

`};`

},

});

export type AppRouter = typeof appRouter;

With Yup​

tsx

import * as trpc from '@trpc/server';

import * as yup from 'yup';

// [...]

export const appRouter = trpc.router<Context>().query('hello', {

input: yup.object({

`text: yup.string().required(),`

}),

resolve({ input }) {

`return {`

  ``greeting: `hello ${input?.text ?? 'world'}`,``

`};`

},

});

export type AppRouter = typeof appRouter;

With Superstruct​

tsx

import * as trpc from '@trpc/server';

import * as t from 'superstruct';

// [...]

export const appRouter = trpc.router<Context>().query('hello', {

input: t.object({

`/**`

 `* Also supports inline doc strings when referencing the type.`

 `*/`

`text: t.defaulted(t.string(), 'world'),`

}),

resolve({ input }) {

`return {`

  ``greeting: `hello ${input.text}`,``

`};`

},

});

export type AppRouter = typeof appRouter;

Method chaining​

To add multiple endpoints, you must chain the calls

tsx

import * as trpc from '@trpc/server';

// [...]

export const appRouter = trpc

.router<Context>()

.query('hello', {

`resolve() {`

  `return {`

    ``text: `hello world`,``

  `};`

`},`

})

.query('bye', {

`resolve() {`

  `return {`

    ``text: `goodbye`,``

  `};`

`},`

});

export type AppRouter = typeof appRouter;